New Furnace (Boiler)

My furnace, which is  boiler, quit working last night.  I had the thermostat set at 70 and the temperature this morning was only 60.  I called the plumber that installed it, Gerard Plumbing and Heating, and they came out.  He messed with some wires, and it started up.  That was 6 hours ago, and it's only 64 in here now.  The radiators and the pipes and actual boiler are lukewarm to the touch.  The guy told me it was in bad condition.  It is 30 years old.  Right now, it is cold in the house and I have two space heaters trying to stay warm.  Especially worried about the cats, that are all elderly, and Feisty who is asthmatic and is going to the vet tomorrow.  Today's bill was $79.  I tried to get assistance from LIHEAP but was turned down.  The guy from Gerard called me about a new one and I applied for credit and was turned down.  All my cards are maxed out.  He quoted me $4600 something and I asked for a Senior citizen discount, and that brought the total down to $4370, and he will credit the $79 I paid, bringing it down to $4291.  I had to give him a down payment and it took my whole social security check, plus whatever else I could scrape together.  This was money I had to pay my bills and living expenses.  I have no idea how I am going to come up with the rest.  I really hate doing this - I have always been self sufficient, and this past year has been really rough for me.  So I'm doing this Go Fund Me at a couple friends suggestions.  I also have paypal, and not sure, but perhaps Gerard will take a direct payment.  Thanking you all a million times over.  I broke down today - been crying off an on all day.